The 49-year-old actress - who has not worked on a movie since she sought treatment in rehab at the beginning of the year - is set to star as the mother of Elizabeth Olsen's character in the movie, which will also feature Dakota Fanning and Peter Sarsgaard.

Dakota and Elizabeth will play best friends who make a pact to lose their virginity during their first summer after high school, but the pair find their friendship is tested when they both fall for the same guy, Deadline reports.

Demi was due to play feminist Gloria Steinem in 'Lovelace' - a movie about real-life porn actress Linda Lovelace - but she was forced to pull out of the role in January, citing a ''personal crisis''.

Heidi Jo Markel - who is producing the motion picture with Jim Young and Laura Rister - previously said: ''It was a shock and a concern for all of us.

''We got a call from [Moore's representative] on Tuesday morning and said, 'There's been a personal crisis and we need to let you know that.' And we were clueless. We had no idea what it entailed. We just knew she was out, that there was probably a health concern, and to move on.''

Demi was replaced by Sarah Jessica Parker, and the 'Striptease' star was said to have been ''devastated'' about losing the part.